Tension between Israel and Gaza is escalating with a dozen rockets being fired into Israel from the Gaza Strip in retaliation for overnight air strikes ordered by Jerusalem.

Hamas launched around 12 rockets into southern Israel on Friday, seriously injuring one person. The group claimed it was response to the Israeli air strikes on the south of Gaza overnight, which reportedly killed one teenager and left 17 injured.

Police across Israel are level three out of four alert with forces preparing to quell any violence during Friday prayers in Jerusalem, which are traditionally a mass event.

Earlier the Voice of Palestine radio station announced that access to Jerusalem for Palestinians from the West Bank was closed.

The Israeli military confirmed the night raids, saying it had targeted a weapons’ manufacturing site, two smuggling tunnels, a "terror tunnel" and several other sites in the wake of deadly attacks on Israeli vehicles on Thursday, and rocket attacks on southern Israel.

"The Israeli Defense Forces will not tolerate any malicious attempt to harm Israeli civilians and IDF soldiers, and will not hesitate to respond with strength and determination to any element that uses terror against the State of Israel and until calm is restored," it said in a statement as cited by the Agence France-Presse on Friday.

The hostilities began on Thursday when eight Israelis died and 25 were injured in a number of assaults on a normally tranquil desert road near Eilat City. At least seven of the assailants were killed in the course of a massive manhunt launched by Israeli forces along the Egyptian border.

­Gaza-based political analyst Hani al-Basoos, thinks it is significant that the violence comes just weeks before a UN vote on Palestinian statehood.

“I think the Israeli side is trying to use this attack as a pretext to launch more militarized acts against the Palestinian civilians and the Palestinian factions,” he said. “And I think the Israeli military would like to jeopardize any Palestinian efforts to go to the United Nations to seek a Palestinian state.”

“All Palestinian political factions have denied any link or responsibility for this attack on the Israeli side,” he added. “All Palestinian political factions and the Palestinian Authority are trying to call for calm and trying to call for a cease-fire with the Israeli side in order to prevent any attack against Gaza or the West Bank by the Israeli military forces and in order to give a chance for the Palestinian Authority to go to the UN next month to seek a Palestinian state.”

­Israeli counterterrorism expert Ely Karmon agrees that the escalation of violence is in some way connected to the upcoming UN vote on Palestinian statehood. But who exactly wants to sabotage the process is not an easy question to answer.

“There are various Palestinian organizations, and I think that some of them are not interested in a separate Palestinian state,” he said. “They want to destroy Israel and have one Palestinian state. So from their point of view, the declaration or the decision of the United Nations is irrelevant – and perhaps even damaging.”

“By the way, this is also the point of view of some countries like Iran and Syria,” he added. “So it is possible that here we have an operation that is exactly intended to sabotage the Palestinian Authority’s intention to raise the question at the United Nations.”